This invention is in the field of heating systems and particularly systems employing a conventional forced air furnace and an auxiliary solid fuel burning heater.
Much combustible solid material, including wood, is wasted by the average household thus throwing an unnecessarily heavy demand on conventional furnace systems which use scarce and expensive fuels. A system for efficiently using such waste materials for heating would not only help in preserving a clean environment but would also reduce the demand for scarce and expensive fuels.
It has already been proposed to combine solid fuel and fluid fuel furnaces, to be used selectively for heating an enclosure. U.S. Pat. No. 3,834,619 proposes an arrangement wherein an enclosed fireplace may be operated to heat air for distribution through the ducts of a conventional furnace. U.S. Pats. 2,525,400; 3,066,655; 3,994,276 and 4,020,822 all disclose unitary furnace structures capable of deriving heat from different selected sources. In each of the above patents, however, a single blower is used. The use of a single blower in such a system as that of U.S. Pat. No. 3,834,619 means that much of the heat produced by the auxiliary burner is wasted and lost in heating the structure of the conventional furnace through which it is drawn.